A mirror of the official Linux kernel repository just in case
Go to file
Kumar Kartikeya Dwivedi aaa619ebcc bpf: Refactor check_btf_func and split into two phases
This patch splits the check_btf_info's check_btf_func check into two
separate phases.  The first phase sets up the BTF and prepares
func_info, but does not perform any validation of required invariants
for subprogs just yet. This is left to the second phase, which happens
where check_btf_info executes currently, and performs the line_info and
CO-RE relocation.

The reason to perform this split is to obtain the userspace supplied
func_info information before we perform the add_subprog call, where we
would now require finding and adding subprogs that may not have a
bpf_pseudo_call or bpf_pseudo_func instruction in the program.

We require this as we want to enable userspace to supply exception
callbacks that can override the default hidden subprogram generated by
the verifier (which performs a hardcoded action). In such a case, the
exception callback may never be referenced in an instruction, but will
still be suitably annotated (by way of BTF declaration tags). For
finding this exception callback, we would require the program's BTF
information, and the supplied func_info information which maps BTF type
IDs to subprograms.

Since the exception callback won't actually be referenced through
instructions, later checks in check_cfg and do_check_subprogs will not
verify the subprog. This means that add_subprog needs to add them in the
add_subprog_and_kfunc phase before we move forward, which is why the BTF
and func_info are required at that point.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230912233214.1518551-6-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-16 09:34:21 -07:00
arch bpf: Implement BPF exceptions 2023-09-16 09:34:21 -07:00
block for-6.6/block-2023-08-28 2023-08-29 20:21:42 -07:00
certs certs: Reference revocation list for all keyrings 2023-08-17 20:12:41 +00:00
crypto This update includes the following changes: 2023-08-29 11:23:29 -07:00
Documentation bpf: expose information about supported xdp metadata kfunc 2023-09-15 11:26:58 -07:00
drivers Including fixes from netfilter and bpf. 2023-09-07 18:33:07 -07:00
fs ntfs3: drop inode references in ntfs_put_super() 2023-09-07 10:23:37 -07:00
include bpf: Implement BPF exceptions 2023-09-16 09:34:21 -07:00
init workqueue: Changes for v6.6 2023-09-01 16:06:32 -07:00
io_uring for-6.6/io_uring-2023-08-28 2023-08-29 20:11:33 -07:00
ipc Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
kernel bpf: Refactor check_btf_func and split into two phases 2023-09-16 09:34:21 -07:00
lib bpf/tests: add tests for cpuv4 instructions 2023-09-15 17:16:57 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm Seven hotfixes. Four are cc:stable and the remainder pertain to issues 2023-09-05 12:22:39 -07:00
net bpf: expose information about supported xdp metadata kfunc 2023-09-15 11:26:58 -07:00
rust Documentation work keeps chugging along; stuff for 6.6 includes: 2023-08-30 20:05:42 -07:00
samples selftests/bpf: trace_helpers.c: Optimize kallsyms cache 2023-09-08 16:22:41 -07:00
scripts Including fixes from netfilter and bpf. 2023-09-07 18:33:07 -07:00
security Three cleanup patches, no behavior changes. 2023-09-04 10:38:35 -07:00
sound This pull request contains the following changes for UML: 2023-09-04 11:32:21 -07:00
tools bpf: Implement BPF exceptions 2023-09-16 09:34:21 -07:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt ARM: 2023-09-07 13:52:20 -07:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: rename binkernel.spec to kernel.spec 2023-07-25 00:59:33 +09:00
.mailmap for-linus-2023083101 2023-09-01 12:31:44 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS USB: Remove Wireless USB and UWB documentation 2023-08-09 14:17:32 +02:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: Add myself for ARM32 BPF JIT maintainer. 2023-09-15 17:16:57 -07:00
Makefile Kbuild updates for v6.6 2023-09-05 11:01:47 -07:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.